/**
 * @author       Richard Davey <rich@photonstorm.com>
 * @copyright    2016 Photon Storm Ltd.
 * @license      {@link https://github.com/photonstorm/phaser/blob/master/license.txt|MIT License}
 */

/**
 * An Image Collection is a special tileset containing mulitple images, with no slicing into each image.
 *
 * Image Collections are normally created automatically when Tiled data is loaded.
 *
 * @class Phaser.ImageCollection
 * @constructor
 * @param {string} name - The name of the image collection in the map data.
 * @param {integer} firstgid - The first image index this image collection contains.
 * @param {integer} [width=32] - Width of widest image (in pixels).
 * @param {integer} [height=32] - Height of tallest image (in pixels).
 * @param {integer} [margin=0] - The margin around all images in the collection (in pixels).
 * @param {integer} [spacing=0] - The spacing between each image in the collection (in pixels).
 * @param {object} [properties={}] - Custom Image Collection properties.
 */
Phaser.ImageCollection = function (name, firstgid, width, height, margin, spacing, properties)
{
    if (width === undefined || width <= 0) { width = 32; }
    if (height === undefined || height <= 0) { height = 32; }
    if (margin === undefined) { margin = 0; }
    if (spacing === undefined) { spacing = 0; }

    /**
     * The name of the Image Collection.
     * @property {string} name
     */
    this.name = name;

    /**
     * The Tiled firstgid value.
     * This is the starting index of the first image index this Image Collection contains.
     * @property {integer} firstgid
     */
    this.firstgid = firstgid | 0;

    /**
     * The width of the widest image (in pixels).
     * @property {integer} imageWidth
     * @readonly
     */
    this.imageWidth = width | 0;

    /**
     * The height of the tallest image (in pixels).
     * @property {integer} imageHeight
     * @readonly
     */
    this.imageHeight = height | 0;

    /**
     * The margin around the images in the collection (in pixels).
     * Use `setSpacing` to change.
     * @property {integer} imageMarge
     * @readonly
     */
    // Modified internally
    this.imageMargin = margin | 0;

    /**
     * The spacing between each image in the collection (in pixels).
     * Use `setSpacing` to change.
     * @property {integer} imageSpacing
     * @readonly
     */
    this.imageSpacing = spacing | 0;

    /**
     * Image Collection-specific properties that are typically defined in the Tiled editor.
     * @property {object} properties
     */
    this.properties = properties || {};

    /**
     * The cached images that are a part of this collection.
     * @property {array} images
     * @readonly
     */
    // Modified internally
    this.images = [];

    /**
     * The total number of images in the image collection.
     * @property {integer} total
     * @readonly
     */
    // Modified internally
    this.total = 0;
};

Phaser.ImageCollection.prototype = {

    /**
     * Returns true if and only if this image collection contains the given image index.
     *
     * @method Phaser.ImageCollection#containsImageIndex
     * @param {integer} imageIndex - The image index to search for.
     * @return {boolean} True if this Image Collection contains the given index.
     */
    containsImageIndex: function (imageIndex)
    {
        return (
            imageIndex >= this.firstgid &&
            imageIndex < (this.firstgid + this.total)
        );
    },

    /**
     * Add an image to this Image Collection.
     *
     * @method Phaser.ImageCollection#addImage
     * @param {integer} gid - The gid of the image in the Image Collection.
     * @param {string} image - The the key of the image in the Image Collection and in the cache.
     */
    addImage: function (gid, image)
    {
        this.images.push({ gid: gid, image: image });
        this.total++;
    }

};

Phaser.ImageCollection.prototype.constructor = Phaser.ImageCollection;
